UPDATE 1-IEA: $70-$90 price needed for unconventional oil

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SINGAPORE Nov 2 (Reuters) - An oil price range of $70-90 per barrel is needed to stimulate investment in unconventional oil resources, Nobuo Tanaka, executive director of the International Energy Agency (IEA), said on Tuesday.

"For unconventional oil sources like oil sands, this level ($70-$90) is necessary for corporations to invest," Tanaka told Reuters on the sidelines of a press conference.

"But does this warrant healthy economic growth? It's an interesting question. We don't know the answer."

Tanaka said that what the IEA is hearing from companies and producers is that $70-$90 is the desired price range.

"The oil price is a very important signal. If it is too low, there's a lack of incentive to invest in alternative sources of energy. If it is too high, it creates a problem. So the price should be moderate." (Reporting by Jennifer Tan; Editing by Michael Urquhart)